Open AccessMeasurement of modular values and connection to the annihilation operator
Author(s) -
Xiaogang Li,
Jiancun Gao
Publication year - 2020
Publication title -
europhysics letters
Language(s) - English
Resource type - Journals
SCImago Journal Rank - 0.625
H-Index - 165
eISSN - 1286-4854
pISSN - 0295-5075
DOI - 10.1209/0295-5075/131/50003
Subject(s) - observable , operator (biology) , quantum entanglement , connection (principal bundle) , annihilation , modular design , physics , measure (data warehouse) , coupling (piping) , creation and annihilation operators , quantum , weak measurement , quantum mechanics , quantum tomography , theoretical physics , quantum state , computer science , mathematics , mechanical engineering , biochemistry , chemistry , geometry , repressor , database , transcription factor , engineering , gene , operating system
Modular value of an observable of a pre- and postselected quantum system is a concept similar to weak value, but in contrast to describing only weak coupling, it can describe the coupling of any strength but only for qubit meters, so it may be used more widely in some scenarios. Besides, modular value has been proved to have advantages on measuring weak values of nonlocal joint observables and nonlocal entanglement states. In this paper, we extend the work of J. S. Lundeen and K. J. Reschb on connection between the measured values of multiparticle observables of a pre- and postselected quantum system and annihilation operator by modular value and give their relation. Based on the above, we propose a new method different from tomography to measure modular values, and we find that our annihilation operator measurement (AOM) method can significantly reduce the number of measurements from O (4 n ) to O (2 n ) compared with the original tomography method.